A system for establishing two-way calls between a radio and a phone system is provided. The system comprises at least one control station for exchanging messages with the radio, at least one interconnect control station, or pair of interconnect control stations, for communicating audio signals to and from the radio over a communication channel comprising respective transmit and receive frequencies, and a gateway for exchanging messages with the phone system, the control station and the at least one interconnect control station, or pair of interconnect control stations, causing the radio to switch to the communication channel whereby audio is transmitted from the phone system to the radio over the transmit frequency and audio as well as DTMF is transmitted from the radio to the phone system for activating special features of the phone system.